The House side of the U.S. Capitol building was temporarily closed Thursday morning after an apparent asbestos accident.

But after hazardous material response teams arrived on the scene and conducted air testing, Fox News is told the tests came back negative. Fox News is also told nobody was injured in the accident overnight."

Fox News is told workers were removing asbestos overnight when something fell. Parts of the House side were closed Thursday morning, but it later returned to normal operations.

Morning debate in the House was canceled over what the speaker's office described as an "industrial accident."

The incident did not affect the Senate side, and nearby House office buildings are still open and accessible.

Fox News' Chad Pergram contributed to this report.